反应详情

To a solution of 944 mg (2.74 mmoles) of the title product of Example 12 in 20 ml of acetic acid is added 20 ml of concentrated hydrochloric acid. The mixture is stirred at reflux for 6 hours and then cooled to room temperature. After azeotropic distillation of most of the acetic acid with toluene, water is added and the mixture is extracted first with 50/50 diethyl ether/toluene, and then further extracted twice with toluene. The combined organic extracts are washed with aqueous sodium bicarbonate and then brine, dried over sodium sulfate, filtered, and evaporated. Chromatography of the residue over silica gel using mixtures of ethyl acetate and hexane as eluents gives the title compound.

1. temperatureat reflux for 6 hours
2. distillationAfter azeotropic distillation of most of the acetic acid with toluene, water
3. additionis added
4. extractionthe mixture is extracted first with 50/50 diethyl ether/toluene
5. extractionfurther extracted twice with toluene
6. washThe combined organic extracts are washed with aqueous sodium bicarbonate
7. dry with materialbrine, dried over sodium sulfate
8. filtrationfiltered
9. customevaporated